1. Field of Invention
This invention relates generally to vehicle surveillance and recording systems, and in particular to a system of this type in which images and audio are yielded by cameras placed at various positions on the vehicle. At least two recording devices record the output of the cameras. One recording device records a thirty minute high resolution image. A second recording device records a two hour lower resolution image. Both recording devices compress the data while recording. The output signals unloaded from the recording devices are selectively fed into an on-board transmitter to modulate a carrier that is radiated from the vehicle and intercepted by an active communications satellite. The output signals are being fed only under certain conditions. One condition is to provide a switch under the control of an individual having operational control. The other condition is under the provision of a device which switches on automatically when certain predetermined physical parameters occur such as when a preselected gravitational force or other parameter has been exceeded.
2. Status of Prior Art
There has of late been a number of highly publicized airplane catastrophes in which as a result the airplane crashes into ocean waters and becomes submerged. Such catastrophes have heightened public concern with aircraft safety. It has also raised relatively serious questions regarding the effectiveness of existing techniques for determining the cause of an aircraft disaster.
The principal means heretofore available to an investigator of an aircraft disaster are flight recorders, commonly known as xe2x80x9cblack-boxesxe2x80x9d. In a commercial aircraft, there are usually two such black boxes, one being a recorder of instrument panel data, the other a recorder of the voices of the flight crew.
Each box is designed to withstand the rigors of a catastrophic plane crash. While the black boxes can usually be recovered without difficulty when the plane crashes on land, it is much more difficult to recover these boxes should the plane crash in ocean waters and sink to the ocean bed.
Black box recorders provide useful information, such as air speed, altitude, heading and vertical acceleration. They record any conversation of the crew in the cockpit and in the flight deck area. Such conversations may reveal what the crew believed to be taking place when an incident occurs resulting in the disaster.
As pointed out in the Feher U.S. Pat. No. 4,816,829, black box data is inadequate for a complete analysis of the conditions prevailing at the time of an accident. Thus, while the airplane instrumentation is monitored and recorded by a black box, external control elements on the airplanes are not monitored, yet what happened to a control element may account for the accident.
In the surveillance system disclosed in the Feher patent, video cameras capture optical images of portions of the plane exterior, while other video cameras capture optical images of portions of the aircraft interior, and also that of the crew. These images are recorded in a protective enclosure within the aircraft designed to survive a crash. Feher provides a telemetry device to transmit the video images to a ground recording station.
A serious drawback of the Feher surveillance system is that the ability of the plane to transmit the video images which monitor the flight is strictly limited to its range of transmission. Thus while the ground recording station may be able to pick up signals transmitted from the plane when the plane is within 300 miles of the recording station it may not be able to pick up these signals when the distance is much greater. Moreover, such transmission from a plane is affected by change in the ionosphere in the Earth""s upper atmosphere.
The Fujimoto U.S. Pat. No. 5,283,643 notes that black boxes are not suitable for small aircraft. Instead of black boxes, the small plane is provided with a video camera in the cockpit and a video camera facing the nose of the fuselage to provide image information that is fed to a video recorder. However, whatever video information is recorded remains on the plane, hence in the event of a crash, it may be difficult to recover such a recording. The Bellman et al U.S. Pat. No. 4,839,439 discloses an aircraft surveillance system having audio as well as video sensors placed in the plane interior to produce signals which are transmitted to a ground recording station. While this system is intended to monitor what is taking place on the plane, and the recordings at the ground station will survive a crash, the system is limited in its effectiveness to a relatively short distance between the transmitting plane and the receiving ground station.
The patent to Lee U.S. Pat. No. 5,742,335 progresses a step further by transmitting the signals from on board and plurality of differently positioned video cameras to an active communications satellite. The satellite relays the signals to a ground recording station whose stored recording of the real time images from the cameras is available to investigators should an accident or other incident occur in the course of the flight. The system includes at least four video cameras, the first of which has an audio function and is trained on the flight crew in the cockpit of the plane. The second video camera is focused on the instrument panel and controls in the cockpit. The third camera, which has an audio function looks into the passenger cabin while the fourth camera is mounted on top of the aircraft rudder to observe exterior surface control movements, such as those of flaps, ailerons and elevators.
In view of the foregoing, the main object of this invention is to provide a vehicle surveillance and recording system having cameras both at interior and exterior positions on the vehicle to monitor the conditions prevailing in the course of a trip by the vehicle, the signals produced by the cameras being recorded in the vehicle and selectively transmitted to an active communications satellite from which it is transmitted to a ground station, whereby in the event of a disaster, an investigator is given access to the ground station recording to determine the cause of the disaster.
More particularly, an object of this invention is to provide a system of the above type in which image and/or audio signals produced by the cameras are transmitted to an active communication satellite which relays these signals to a ground recording station whereby the signals are received by the ground station regardless of its distance from the transmitting vehicle.
A significant advantage of the invention is that unlike black boxes, it affords visual as well as acoustic data. The invention overcomes the reluctance on the part of the crew of the vehicle to have their activities recorded unless a manually operated switch is turned on to transmit the captured recording on the vehicle to the active communications satellite or conditions exist and appropriate sensors respond to certain conditions which have occurred whereby said recordings are transmitted to the active communications satellite. By employing loop recorders only portions of a trip can be recorded and transmitted, thereby limiting any untoward intrusions to conventional occurrences.
Briefly stated, these objects are attained by a vehicle surveillance and recording system and adapted to monitor conditions prevailing in the course of a trip and provided for this purpose with image producing cameras placed at different positions on the vehicle. Two recording devices record the output of the device. One device records a thirty minute high resolution image. The second device records a two hour lower resolution image. Both recording devices compress the data while recording. The output signals unloaded from the recording devices are selectively fed into an on-board transmitter to modulate a carrier that is radiated from the vehicle and intercepted by an active communications satellite. The output signals are being fed only under certain conditions. One condition, as has been stated, is to provide a switch under the control of an individual charged with operational control. The other condition is under the provision of a device which switches on automatically when certain predetermined physical parameters occur such as when a preselected gravitational force or other parameter has been exceeded.